Mirror-type dental instrument with vacuum means for keeping a dry surface



Sept. 4, 1962 v. J. PISCITELLI 3,052,031

MIRROR-TYPE DENTAL INSTRUMENT WITH VACUUM MEANS FOR KEEPING A DRY SURFACE Filed March 31, 1960 2 Sheets-Sheet 1 Sept. 4, 1962 v. J. PISCITELLI 052,031

E DENTA 3 MIRROR-TYP L INSTRUMENT WITH VACUUM MEANS FOR KEEPING A DRY SURFACE Filed March 51, 1960 2 Sheets-Sheet 2 United States Patent Ofifice $352,031 Patented Sept. 4, 1962 3,652,031 MIRROR-TYPE DENTAL INSTRUMENT WITH VACUUM MEANS FOR KEEPING A DRY SURFACE Vincent J. Piscitelli, 828 1st St., La Salle, Ill. Filed Mar. 31, 196i Ser. No. 19,019 2 Claims. (CI. 3269) This invention relates to a dental instrument, and more particularly to a dental mirror including nozzle means providing an air shield which positively prevents materials such as the mist and water propelled from high speed and ultra high speed rotary drills or the like from collecting on the mirror surface.

Since my invention utilizes the principles of the venturi to increase the velocity of the air that passes through the nozzle, a pressure differential is developed as the air leaves the nozzle in accordance with the principles developed by Bernoulli, and consequently a vacuum is created around particular areas of the mirror. The location of this vacuum condition is dependent in part upon the placement of the nozzle relative to the mirror face. Thus, placing the nozzle close to the edge of the mirror draws air from beneath the mirror by eliminating vacuum areas which might otherwise permit some materials to be deposited on the mirror. In accordance with my invention, I also provide for complementary vacuum means to increase the effectiveness of the mirror, and dispose the terminal portions of the nozzle structure in a convex curve extending reversely of the adjacent edge of the mirror.

Accordingly, it is an object of the present invention to provide a dental instrument which is exceptionally effective in protecting the surface of the mirror under all operating conditions.

Another object of the invention is to provide a dental instrument as described wherein the air is led from underneath the mirror by air directed across the face of the mirror, to provide a reliable shielding action for the mirror face.

Another object of the invention is to provide conduit means for leading the air from beneath a dental mirror to a location adjacent nozzle passages in the conduit means for directing the air across the face of the mirror so as to improve efiiciency of the device.

Another object of the invention is to provide 'vacuum means cooperating with the vacuum at the base of the mirror to further augment the efficiency of the device.

Another object of the invention is to provide vacuum means which are effective to operate upon the sides of the mirror to maintain a cleared condition thereof.

Other objects and advantages of the invention will become apparent as the description proceeds in accordance with the drawings, in which:

On the drawings:

FIGURE 1 is a side elevational view of the dental instrument according to the present invention;

FIGURE 2 is an enlarged fragmentary top plan view of ;valve means for operating the dental instrument of the invention;

FIGURE 3 is a vertical sectional view of the dental instrument of the invention;

FIGURE 4 is a vertical sectional View of another embodiment of the invention;

FIGURE 5 is a top plan view, in fragmentary form and partially in horizontal section, of the structure shown in FIGURE 4;

FIGURE 6 is a vertical sectional view taken along the line VIVI of FIGURE 5;

FIGURE 7 is a fragmentary top plan view, partially in vertical section of another embodiment of the invention;

FIGURE 8 is a vertical sectional view taken along the line VIIIVIII of FIGURE 7;

FIGURE 9 is a fragmentary, top plan view, partially in horizontal section of another embodiment of the invention;

FIGURE 10 is a vertical sectional view taken along the line XX of FIGURE 9;

FIGURE 11 is a fragmentary top plan view, partially in horizontal section, of another embodiment of the invention;

FIGURE 12 is a vertical sectional view taken along the line XII--XII of FIGURE 11;

FIGURE 13 is an enlarged fragmentary vertical sectional view of another embodiment of valve means for controlling the nozzle operation of the dental instrument of the invention;

FIGURE 14 is a vertical sectional view taken along the line XIVXIV of FIGURE 13;

FIGURE 15 is a view corresponding to the view of FIGURE 14 but showing the valve in closed position; and

FIGURE 16 is a fragmentary top plan view of another embodiment of the invention.

As shown on the drawings:

Referring now to the drawings, a dental instrument is shown in FIGURES 1 through 3 according to the present invention, which is designated generally by reference numeral 10, and comprises an elongated handle 11 having a valve fitting 12 threadedly secured thereto at one end thereof, a conduit nipple 13 threadedly secured thereto at the other end thereof and a nozzle 14 threadedly secured to the valve fitting 12. The nozzle 14 also provides a bracket for a mirror 15, as hereinafter further described.

As shown more particularly in FIGURE 3, the handle structure 11 has formed therethrough a bore 16 in communication with a suitable hose 17, resiliently engaging the nipple 13 of FIGURE 1. The bore 16 is configured at the end opposite the fitting 13 so as to threadedly receive a valve :18, which in itself may b relatively conventional in construction and is preferably similar to a tire valve element.

In order to control the valve 18, the valve fitting 12 has a transverse cylindrical chamber 19 formed therein in communication with the reduced end of the bore 16 receiving the valve 18, the fitting 12 also defining a passage 20 leading from the chamber 19 to the nozzle 14. A valve actuating button 21 is slidably received in the chamber 19 which includes a cylindrical body portion 22 having an inverted conical camming surface 23, a centrally depending actuating rod 24 and a circular guide and latch plate 25 formed integrally on the end of the rod member 24 in coaxial perpendicular relationship therewith. The button 21 may have a bearing surface 26 of relatively wide diameter preferably provided with directional indicia such as the arrow 27 shown in FIGURE 2, to indicate the locked or unlocked position thereof. In the position shown in FIGURES 1 through 3, the valve is in the off position.

In the inoperative or off position shown in FIGURE 3, the locking plate 25 engages a valve stem 28 and a perpendicular disk 28a thereon for the valve 18, so that the button 21 is retained from accidental movement out of the valve fitting 12. When the button is manually depressed, however, the camming surface 23 normally moves the valve stem 28 into the valve 18, to open the valve against resilient means contained therein (not shown) and also moves the valve cap 29 off its valve seat, as understood by those skilled in the art. It will be understood that the conical surface 23 is dimensioned and configured to be cammed upwardly by the said resilient action of the valve stem 28, to move the valve automatically to its closed position.

However, in order to provide for locking the valve in its open position without the need for attention by the operator, the valve-actuating button 21 is provided with a cutout portion defining a vertical shoulder 30 which is effective to prevent closing of the valve 18 when the valve button is rotated 180 manually from the position shown in FIGURES 2 and 3. Thus the disk or head 28a of the valve stem 28 will abut the shoulder 30 in coplanar relationship so that no camming is produced and the valve button is retained by the pressure of the valve stem in the desired open position.

In order to direct a shield of air across the upper face of the mirror 15, the nozzle member 14 forms a passage 31 in communication with the bore 20 and the valve 12, the passage 31 being preferably convergent and leading to a nozzle passage structure 32 of reduced cross sectional area having a relatively wide fan shaped characteristic. Thus, the nozzle passage structure 32 is of a generally divergent configuration, as hereinafter further described, and has a convex terminal portion 33 which is reversely curved relative to the adjacent curve of the mirror 15, to augment the action of the air shield produced thereby.

In accordance with the invention, the end of the passage 32 is spaced from the mirror a predetermined distance such that the pressure conditions produced by the high velocity of the air as it emanates therefrom effect a vacuum condition in back of the mirror and adjacent the nozzle passage structure 32. This vacuum condition will tend to draw air from beneath the mirror, thereby improving the air shielding and preventing fluid and materials from collecting on the mirror face.

The bottom portion of the nozzle 14 may have an intcgra'lly formed female locking bracket 34 to afford selective removal and replacement of the mirror 15, and may include a male insert or inserts 35 therein to act as a shim to hold the mirror on the instrument until it is desired to remove it. However, it is preferred that the bracket 34 define a passage 36 in conjunction with the bottom face of the mirror, with the sides of the bracket 34 defining the sides of the passage, or with the shim means 35 affording a passage therebetween. The flow conduit 36 thus formed extends forwardly from the rear of the mirror for a distance which is preferably less than half of the diameter of the mirror.

A passage is formed from the passage 36 to the terrninal portion of the nozzle portion 32 by means of one or more apertures 37 at the bottom of the bracket 34 and one. or more apertures 38 forming a slot between the terminal edge 33 of the nozzle portion 32 and a shelf 38a adjacent the mirror 15. Thus, as indicated by the arrows, a continual flow of air will be drawn through the passage 36, the aperture 37 and the aperture or slot 38 by the above-described vacuum at the terminal portion of the nozzle passage structure 32. The vacuum provided by the flow through the passage 36 increases the effectiveness of the shield afforded by the flow from the passage or nozzle structure 32 across the top of the mirror.

In order to assist in maintaining a cleared condition across the top face of the mirror 15, a passage 39 may be provided in the nozzle 14, which preferably extends in subjacent relationship to the passage 31 and into the area immediately above the aperture 37. Thus the air drawn through the passage 39 may also pass through the port 38 in a manner which aids in the movement of air from beneath the mirror.

Also in accordance with the invention, and as shown in the embodiment of FIGURES 4 through 6, a passage 31a may be formed in the structure 14a having a portion 32a corresponding to the portion 32 and a pair of lower conduits 43 and 44 formed in part by the shelf 34a. Air passing from the passage 31a downwardly through the lower conduits 43 and 44 will therefore draw air and moisture by vacuum action from the upper face of the mirror through branching side passages 45 and 46 which lead to a semi-circular hood 42 surrounding the mirror in spaced relation from the nozzle to a forward portion of the mirror with which it is in contact and partially underlying the mirror. The passages 43 and 44 lead upwardly to the convex slot 38a joining the conduits 43 and 44 with the passage 31a. Slots 47 and 48 are provided to communicate a venturi induced, vacuum to the hood 42, by the passage of air from the passage 31a through conduits 43 and 44. The resultant vacuum within the hood is therefore peculiarly effective to maintain a clear condition across the face of the mirror.

Referring now to FIGURE 16, another embodiment of the invention is shown wherein an external source of vacuum is applied to cooperate with air flow across the mirror face and to maintain the cleared condition of the mirror. In this embodiment, an upper passage 32b feeds air over the upper face of the mirror 15 and a vacuum tube 49a is connected to a lower passage 3% which branches at 41 in the shelf structure 3% beneath the mirror to openings within the hood 42. The positive vacuum thus applied assures that a desired amount of clearing action will be produced across the face of the mirror to complement the action of the air ejected from the passage 32b, although it will be appreciated that the venturi and vacuum action afforded in the embodiment FIGURES 4-6 is also entirely adequate.

Referring now to FIGURE 7 and FIGURE 8, another form of the invention is shown wherein the described venturi action is provided by needle nozzles 49 which fan out in divergent relationship from a passage corresponding to the passage 31 in FIGURE 3 having a convex terminal portion 33. The needle nozzles '49 may have their terminal portions aligned in a convex configuration having a reverse curvature with respect to the adjacent edge of the mirror 15. It will be seen that they are particularly effective to direct a strong stream of compressed air across the face of the mirror. The slot or opening 38 essentially corresponds to that previously described, and the vacuum action at the bottom portions of the mirror may also be similar. However, as seen in FIGURE 8, no passage corresponding to the passage 39 is provided. The nozzles 49 may either be formed of metal embedded in the surrounding plastic of the nozzle, as shown in FIGURE 8, or otherwise made of a suitable material to provide a relatively small crosssectional diameter for each individual nozzle.

Referring now to FIGURES 9 and 10, another embodiment of the invention is shown, wherein stamped metal formed on a suitable die is utilized for the top and bottom portions of nozzles 50 which diverge similarly to those shown in FIGURE 7. The metal stampings may be fitted in correspondingly shaped recesses in upper and lower portions 51 and 52 being suitably cemented in faceto-face abutting relation or otherwise sealed in alignment as shown in FIGURE 10. Because of the accessability afforded by the metal stamping construction of FIGURES 9 and lO, the interior of the passages 50 may be rifled with spiral grooves such as indicated at 50a so that the air may be propelled across the mirror with relatively high velocity. However, it will be appreciated that suitable nozzles could also be formed by means of the upper and lower portions 51 and 52 without any internal metal structure for the said bores 50.

Referring now to FIGURES 11 and 12, yet another embodiment of the invention is shown, which substantially corresponds to that shown in FIGURE 5. In this construction, the nozzle portion 53 is a passage extending continuously both laterally and longitudinally, but which diverges toward the convex terminal edge 33 and the slot 38 adjacent thereto, it being noted that in this embodiment as in the embodiments of FIGURES 7 through 10, no passage such as 39 in FIGURE 3 is used so that the venturi action draws air entirely from beneath the mirror through slot 38 and thence across the mirror with air diverging from the nozzle as hereinabove described. Passage 53 is shown as being formed in an integral nozzle structure 14c.

Referring now to FIGURES 13 through 15, another embodiment of the valve structure of the invention is shown whereby manual rotation of a valve sleeve 54 is effective to control the closing and opening of a valve element 21a. To this end, the nozzle structure 14d defines a circumferential recess 55 to receive the sleeve 54 for angular rotation therein. It will be appreciated, however, that the sleeve 54 may be formed with a continuous internal circumferential boss to be fitted in a groove of smaller dimension than the groove 55 and with the internal surfaces of the sleeve riding on the exterior portions of the nozzle structure 14d in guided relationship. The sleeve 54 may be externally knurled or otherwise constructed for easy manual operation, and defines a cut-out portion 56 which, as seen more particularly in- FIGURE 15, is dimensioned to receive the valve element 21a therethrough in the closed position of the said valve element.

So as to permit easy opening and closing action, the valve member 21a has an arcuate upper surface 57 aligned for engagement by one side or the other of the slot 56. In the form shown, the left hand side of the slot 56 is inclined at an angle corresponding substantially to the angle of curvature of the surface 57 so that When the sleeve 54 is rotated clockwise, the surface 58 of the sleeve will engage the surface 57 of the valve element 21a and cam it downwardly into a position where the valve stem 28 is engaged by the conical surface 23a of the valve member and cammed to open position as hereinabove set forth. This position is shown in FIGURE 14.

There has thus been provided a dental instrument which is particularly effective to maintain a clear condition for the upper surface of a mirror, and which is highly suitable for use with high speed dental drills and the like. Even when a relatively large amount of fluid is present in the areas adjacent to the mirror, the vacuum action afforded in the several embodiments of the invention will draw that fluid around the sides of the mirror and below the mirror to maintain the said clear condition at all times.

The operation of the dental instrument of the invention is simple and reliable, as a result of the valve structure therefor, which may be maintained in open position without any effort on the part of the operator. And because of the clear image afforded under even the most diflicult working conditions, the device can be utilized in an extremely wide variety of dental as well as other applications.

Although I have herein set forth and described my invention with respect to certain specific principles and details thereof, it will be understood by those skilled in the art that these may be varied without departing from the spirit and scope of the invention as set forth in the hereunto appended claims.

I claim. as my invention:

1. In a dental instrument having a handle and a mirror, means for passing compressed air in a fan shaped configuration over a top surface of the mirror, and a valve for controlling the flow of said compressed air comprising a manually actuab'le member having a camming surface thereon, a valve element adapted to be cammed into open position by said camming surface, and a shoulder on said camming surface for engaging said valve element, said valve element being adapted to cam said member to an initial position therefor and said shoulder being engageable by said valve element to retain said valve in open position, said member being manually rotatable about its axis to selectively place said shoulder in position to engage said valve element and to remove said shoulder from said position.

2. In a dental mirror, means forming a planar reflective surface, air discharge means including a nozzle directing a curtain of air in parallel adjacency to said reflective surface from a source at increased pressure, air suction means including openings spaced adjacent said surface but away from said nozzle, passage-forming means connected to said openings, said passage-forming means being connected to said air discharge means in a vent-uri relationship, whereby the vacuum bias imposed on said air suction means will draw air and moisture away from the reflective surface.

References Cited in the file of this patent UNITED STATES PATENTS 1,660,870 Fust Feb. 28, 1928 1,905,633 Feltham Apr. 25, 1933 2,068,660 Curtis Jan. 26, 1937 2,693,338 Grunt Nov. 2, 1954 2,779,100 Claessens Jan. 29, 1957 2,834,109 OHara May 13, 1958 2,843,019 Larson July 15, 1958 2,907,110 OHara Oct. 6, 1959 

